The present invention relates to a towing device for an agricultural apparatus, comprising at least one wheel which is arranged in a front area of the agricultural apparatus and can rotate about an essentially horizontal wheel axle; a link arm which is connected to the wheel axle and is coupled in an articulated manner to a frame arranged on the agricultural apparatus about an essentially vertical first axis; and a draw bar which can be coupled to a towing vehicle.
Large agricultural apparatuses must be provided with more than one wheel axle so that the weight of the apparatus can be distributed over a greater surface area on the ground. An agricultural apparatus with more than one wheel axle and towed by a towing vehicle is more difficult to handle than an agricultural apparatus which is only provided with one wheel axle. A multi-axle agricultural apparatus has a tendency to make sharp turns behind the towing vehicle when the towing vehicle turns, which means that the towing vehicle has to widen the turns and turn with a large turning radius if the towing vehicle and the towed agricultural apparatus are to avoid an obstacle. This has meant that the turning areas in a field tend to be considerably larger compared with an agricultural apparatus which is only provided with one wheel axle. It is also more difficult to reverse with a multi-axle agricultural apparatus compared with a single-axle agricultural apparatus.
There are often narrow passages and obstacles on fields, which increase the requirement for smooth handling of an agricultural apparatus. The driver is forced to drive the towing vehicle back and forth in order to get into the desired position when working of the soil is to begin, leading to unwanted compression of the soil. Since work with agricultural apparatuses is often done under time constraints, the work with a multi-axle agricultural apparatus is extremely demanding on the driver.
The object of the present invention is to increase the manoeuvrability of an agricultural apparatus which is provided with a number of wheel axles, so that the towing vehicle can make sharp turns with a small turning radius without the agricultural apparatus also making excessively sharp turns.
This is achieved using an agricultural apparatus of the type set out in the introduction, in which a control member is arranged between the draw bar and the frame in order to control the pivoting of the link arm about the first axis as the towing vehicle turns, so that the agricultural apparatus turns at least less than the towing vehicle.
With such a towing device, the agricultural apparatus is easy to manoeuvre with the aid of the towing vehicle. The turning areas can be made small, and it is easy to bring the agricultural apparatus to the desired position when cultivation is to begin. It is also easy to reverse the agricultural apparatus since the controlled pivoting of the link arm about the first axis means that the towing vehicle and the agricultural apparatus do not move towards each other.